K++, or more commonly known as KaZaA Lite was an illegal product. The owners and makers of the KaZaA p2p network, Sharman Networks, decided to crack down on KaZaA Lite. They threatened to file charges at the maker of K++, and he decided to shut it down. It was removed from most websites. Since K++ must have a new version made each time a new version of KaZaA is released, Sharman Networks can essentially "outdate" K++ to death. There are still K++ servers running, but they are less frequent, and Sharman is shutting more and more down every day. I have personally noticed that files are getting harder and harder for me (a K++ user) to download.
You can always get the (supposedly) spyware and adware free KaZaA+ from Sharman, but obviously, it's going to cost money.